:root {
  --bg: #f7f8fc;
  --card: #ffffff;
  --text: #1f2937;
  --muted: #6b7280;
  --primary: #4757c7;
  --primary-soft: #eef0ff;
  --good: #16794b;
  --good-soft: #e8f7ef;
  --warn: #a86800;
  --warn-soft: #fff5dd;
  --bad: #b42318;
  --bad-soft: #fdecec;
  --border: #dfe3ec;
  --shadow: 0 10px 28px rgba(31,41,55,.08);
  --radius: 18px;
}
* { box-sizing: border-box; }
html, body { margin: 0; min-height: 100%; background: var(--bg); color: var(--text); font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif; }
button, input, select, textarea { font: inherit; }
button { cursor: pointer; }
button:disabled { cursor: not-allowed; opacity: .55; }
input, select, textarea {
  width: 100%; border: 1px solid var(--border); border-radius: 12px; padding: 12px 14px; background: #fff; color: var(--text);
}
textarea { min-height: 130px; resize: vertical; }
label { display: block; font-weight: 700; margin-bottom: 6px; }
hr.divider { border: 0; border-top: 1px solid var(--border); margin: 18px 0; }
.small { font-size: .88rem; color: var(--muted); }
.muted { color: var(--muted); }
.hidden { display: none !important; }
.app-shell { min-height: 100vh; }
.topbar {
  position: sticky; top: 0; z-index: 20; display: flex; align-items: center; justify-content: space-between; gap: 12px;
  padding: max(12px, env(safe-area-inset-top)) 18px 12px; background: rgba(247,248,252,.95); backdrop-filter: blur(10px); border-bottom: 1px solid rgba(223,227,236,.9);
}
.brand { display: flex; align-items: center; gap: 10px; font-weight: 900; font-size: 1.08rem; min-width: 0; }
.brand > div:last-child { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.brand-badge { width: 36px; min-width: 36px; height: 36px; display: grid; place-items: center; background: var(--primary-soft); border-radius: 12px; }
.version { color: var(--muted); font-size: .8rem; font-weight: 700; }
.main { width: min(1100px, 100%); margin: 0 auto; padding: 22px 16px 40px; }
.hero { text-align: center; padding: 18px 0 8px; }
.hero h1 { margin: 0 0 8px; font-size: clamp(1.7rem, 5vw, 2.6rem); }
.hero p { margin: 0; color: var(--muted); }
.compact-hero { padding-bottom: 18px; }
.grid { display: grid; gap: 16px; }
.profile-grid { grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); margin-top: 22px; }
.card { background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); box-shadow: var(--shadow); padding: 18px; }
.profile-card { text-align: center; min-height: 190px; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 8px; }
.profile-emoji { font-size: 3rem; line-height: 1; }
.small-emoji { font-size: 2.3rem; margin-bottom: 8px; }
.profile-card h3 { margin: 0; font-size: 1.35rem; }
.btn {
  border: 0; border-radius: 12px; min-height: 46px; padding: 11px 16px; font-weight: 800; background: #eef1f6; color: var(--text);
}
.btn:hover { filter: brightness(.98); }
.btn-primary { background: var(--primary); color: white; }
.btn-danger { background: var(--bad-soft); color: var(--bad); }
.btn-good { background: var(--good); color: white; }
.btn-ghost { background: transparent; border: 1px solid var(--border); }
.btn-block { width: 100%; }
.btn-lg { min-height: 54px; font-size: 1.03rem; }
.center-actions { text-align: center; margin-top: 24px; }
.section-title { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin: 8px 0 14px; }
.section-title h2 { margin: 0; }
.assignment-list { display: grid; gap: 12px; }
.assignment-card { display: grid; grid-template-columns: 1fr auto; gap: 14px; align-items: center; }
.assignment-card h3 { margin: 0 0 6px; }
.badges { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 8px; }
.badge { display: inline-flex; align-items: center; min-height: 26px; padding: 4px 9px; border-radius: 999px; background: #f0f2f7; color: #4b5563; font-size: .8rem; font-weight: 800; }
.badge-good { background: var(--good-soft); color: var(--good); }
.badge-warn { background: var(--warn-soft); color: var(--warn); }
.empty { text-align: center; padding: 34px 18px; color: var(--muted); }
.toolbar { display: flex; flex-wrap: wrap; gap: 10px; margin-bottom: 16px; }
.parent-tabs { display: flex; gap: 8px; overflow-x: auto; padding-bottom: 4px; margin-bottom: 18px; }
.tab { white-space: nowrap; }
.tab.active { background: var(--primary); color: white; }
.form-grid { display: grid; gap: 14px; }
.form-row { display: grid; gap: 14px; grid-template-columns: repeat(2, minmax(0,1fr)); }
.check-row { display: flex; gap: 10px; align-items: center; margin: 5px 0; }
.check-row input { width: auto; min-width: 18px; min-height: 18px; }
.inline-label { margin: 0; font-weight: 650; }
.table-wrap { overflow-x: auto; border: 1px solid var(--border); border-radius: 14px; }
table { width: 100%; border-collapse: collapse; background: #fff; }
th, td { padding: 12px; border-bottom: 1px solid var(--border); text-align: left; white-space: nowrap; }
th { font-size: .82rem; text-transform: uppercase; letter-spacing: .03em; color: var(--muted); }
.score { font-weight: 900; }
.score.good, .result-number.good { color: var(--good); }
.score.warn, .result-number.warn { color: var(--warn); }
.score.bad, .result-number.bad { color: var(--bad); }

.subject-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; max-width: 800px; margin: 0 auto; }
.subject-card { appearance: none; width: 100%; color: inherit; font: inherit; text-align: center; min-height: 230px; display: flex; flex-direction: column; align-items: center; justify-content: center; transition: transform .15s ease, box-shadow .15s ease, border-color .15s ease; }
.subject-card:hover { transform: translateY(-2px); border-color: #c8cdea; box-shadow: 0 14px 34px rgba(31,41,55,.12); }
.subject-card h2 { margin: 8px 0 6px; font-size: 1.55rem; }
.subject-icon { font-size: 4rem; line-height: 1; }
.reading-card { background: linear-gradient(180deg, #ffffff, #f7f8ff); }
.math-card { background: linear-gradient(180deg, #ffffff, #f7fcfa); }

.test-shell { min-height: 100vh; background: #f5f6fb; }
.test-header { position: sticky; top: 0; z-index: 10; background: #fff; border-bottom: 1px solid var(--border); padding: 12px 16px; }
.test-header-inner { width: min(1200px,100%); margin: 0 auto; display: flex; align-items: center; gap: 14px; }
.test-title { flex: 1; min-width: 0; }
.test-title h2 { font-size: 1rem; margin: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.progress-wrap { margin-top: 6px; }
.progress-track { height: 8px; background: #e7eaf1; border-radius: 999px; overflow: hidden; }
.progress-bar { height: 100%; background: var(--primary); width: 0; transition: width .2s ease; }
.timer { white-space: nowrap; background: #f0f2f7; padding: 8px 10px; border-radius: 10px; font-variant-numeric: tabular-nums; }
.timer.timer-low { background: var(--bad-soft); color: var(--bad); }
.test-grid { width: min(1200px,100%); margin: 0 auto; padding: 16px; display: grid; gap: 16px; grid-template-columns: minmax(0,1.1fr) minmax(0,.9fr); align-items: start; }
.passage-card { position: sticky; top: 88px; max-height: calc(100vh - 108px); overflow: auto; }
.passage-card h2 { margin-top: 0; }
.passage-text { white-space: pre-wrap; line-height: 1.7; font-size: 1.03rem; }
.question-card { min-height: 460px; display: flex; flex-direction: column; }
.question-number { color: var(--muted); font-weight: 800; margin-bottom: 8px; }
.question-prompt { font-size: clamp(1.2rem, 3vw, 1.55rem); line-height: 1.4; font-weight: 850; margin: 0 0 18px; }
.choice-list { display: grid; gap: 11px; }
.choice { width: 100%; text-align: left; min-height: 58px; padding: 14px 16px; border: 2px solid var(--border); border-radius: 14px; background: #fff; font-weight: 750; color: var(--text); }
.choice.selected { border-color: var(--primary); background: var(--primary-soft); }
.choice-letter { display: inline-grid; place-items: center; width: 30px; height: 30px; border-radius: 999px; background: #eef1f6; margin-right: 10px; }
.choice.selected .choice-letter { background: var(--primary); color: white; }
.question-actions { display: flex; gap: 10px; justify-content: space-between; margin-top: auto; padding-top: 24px; }
.question-actions .btn { min-width: 120px; }

.result-hero { text-align: center; padding: 20px; }
.result-number { font-size: clamp(2.6rem, 12vw, 5rem); font-weight: 950; line-height: 1; margin: 10px 0; }
.result-badge { margin-top: 12px; }
.result-message { margin: 16px auto 0; max-width: 580px; }
.result-actions { display: flex; flex-wrap: wrap; justify-content: center; gap: 10px; margin-top: 18px; }
.review-anchor { scroll-margin-top: 20px; margin-top: 22px; }
.review-list { display: grid; gap: 12px; }
.review-item { border: 1px solid var(--border); border-radius: 14px; padding: 15px; background: #fff; }
.review-item.correct { border-left: 6px solid var(--good); }
.review-item.incorrect { border-left: 6px solid var(--bad); }
.review-item.pending { border-left: 6px solid var(--warn); }
.review-item h4 { margin: 0 0 8px; line-height: 1.35; }
.review-item p { margin: 6px 0; }

.modal-backdrop { position: fixed; inset: 0; z-index: 100; background: rgba(17,24,39,.48); display: grid; place-items: center; padding: 16px; }
.modal { width: min(680px,100%); max-height: min(90vh,900px); overflow: auto; background: white; border-radius: 20px; padding: 20px; box-shadow: 0 24px 70px rgba(0,0,0,.25); }
.modal h2 { margin-top: 0; }
.modal-actions { display: flex; justify-content: flex-end; gap: 10px; margin-top: 18px; }
.preview-box { background: #f7f8fc; border: 1px solid var(--border); border-radius: 14px; padding: 14px; }
.preview-box h3 { margin-top: 0; }
.import-summary { margin-top: 12px; }
.file-drop { border: 2px dashed #b9c1d0; border-radius: 16px; padding: 24px; text-align: center; background: #fafbfe; }
.error-box { background: var(--bad-soft); color: var(--bad); border-radius: 12px; padding: 12px; }
.success-box { background: var(--good-soft); color: var(--good); border-radius: 12px; padding: 12px; }
.toast { position: fixed; z-index: 200; left: 50%; bottom: max(18px, env(safe-area-inset-bottom)); transform: translateX(-50%) translateY(20px); background: #111827; color: white; padding: 11px 16px; border-radius: 12px; opacity: 0; pointer-events: none; transition: .2s ease; max-width: calc(100% - 32px); text-align: center; }
.toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }

.option-strip { display: grid; grid-template-columns: repeat(3, minmax(0,1fr)); gap: 10px; margin-bottom: 16px; }
.option-tile { border: 1px solid var(--border); border-radius: 14px; padding: 12px; display: flex; flex-direction: column; gap: 4px; background: #fafbfe; }
.option-tile span { color: var(--muted); font-size: .82rem; }
.active-option { border-color: #bcc3f3; background: var(--primary-soft); }
.future-option { opacity: .66; }
.metadata-grid { display: grid; grid-template-columns: repeat(3, minmax(0,1fr)); gap: 10px; margin-top: 14px; }
.metadata-grid > div { background: #fff; border: 1px solid var(--border); border-radius: 10px; padding: 10px; display: flex; flex-direction: column; gap: 3px; }
.metadata-grid strong { font-size: .78rem; color: var(--muted); text-transform: uppercase; letter-spacing: .03em; }
.metadata-wide { grid-column: 1 / -1; }
.settings-panel { border: 1px solid var(--border); border-radius: 14px; padding: 12px; background: #fff; display: grid; gap: 5px; }
.student-admin-grid { grid-template-columns: repeat(auto-fit,minmax(280px,1fr)); }
.student-admin-card h3 { margin-top: 0; }
.student-card-actions { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
.settings-card { max-width: 520px; }

@media (max-width: 800px) {
  .test-grid { grid-template-columns: 1fr; }
  .passage-card { position: static; max-height: none; }
  .assignment-card { grid-template-columns: 1fr; }
  .assignment-card .btn { width: 100%; }
  .metadata-grid { grid-template-columns: 1fr 1fr; }
  .option-strip { grid-template-columns: 1fr; }
}
@media (max-width: 620px) {
  .subject-grid { grid-template-columns: 1fr; }
  .subject-card { min-height: 175px; }
  .subject-icon { font-size: 3.2rem; }
  .metadata-grid { grid-template-columns: 1fr; }
  .metadata-wide { grid-column: auto; }
  .test-header-inner { gap: 8px; }
  .timer { padding: 7px 8px; font-size: .88rem; }
}
@media (max-width: 560px) {
  .main { padding: 16px 12px 34px; }
  .card { border-radius: 15px; padding: 15px; }
  .form-row { grid-template-columns: 1fr; }
  .question-actions .btn { min-width: 0; flex: 1; }
  .test-grid { padding: 10px; }
  .test-header { padding: 10px; }
  .brand { font-size: .95rem; }
  .brand-badge { width: 32px; min-width: 32px; height: 32px; }
  .student-card-actions { grid-template-columns: 1fr; }
  .result-actions { flex-direction: column; }
  .result-actions .btn { width: 100%; }
}

/* v1.2 Content & Assignment Creation */
.badge-muted { background: #eceff3; color: #6b7280; }
.badge-new { background: #e0f2fe; color: #075985; }
.assignment-new { border-color: #bae6fd; }
.assignment-heading { display: flex; align-items: center; gap: 9px; flex-wrap: wrap; }
.assignment-heading h3 { margin: 0; }
.clickable-options { grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); }
.clickable-options .option-tile { appearance: none; text-align: left; color: inherit; font: inherit; cursor: pointer; min-height: 106px; }
.clickable-options .option-tile:hover { border-color: #b6bff2; background: var(--primary-soft); transform: translateY(-1px); }
.guide-card summary { cursor: pointer; font-size: 1.03rem; }
.guide-content { margin-top: 16px; }
.guide-action { display: flex; align-items: end; }
.prompt-box { min-height: 210px; font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; font-size: .82rem; background: #f7f8fc; }
.library-title { margin-top: 24px; }
.assignment-library { display: grid; gap: 14px; }
.library-card { display: grid; grid-template-columns: minmax(0,1fr) auto; gap: 16px; align-items: start; }
.library-main { min-width: 0; }
.library-actions { display: grid; grid-template-columns: repeat(2, minmax(90px, 1fr)); gap: 8px; width: 220px; }
.assigned-students { display: flex; flex-wrap: wrap; gap: 7px; margin-top: 11px; }
.student-chip { display: inline-flex; align-items: center; min-height: 30px; padding: 5px 9px; border-radius: 10px; background: #f7f8fc; border: 1px solid var(--border); font-size: .82rem; font-weight: 700; }
.inline-actions { margin-top: 10px; }
.builder-toolbar { display: flex; align-items: center; justify-content: space-between; gap: 16px; position: sticky; top: 70px; z-index: 8; border-color: #d9dcf5; }
.builder-toolbar h2 { margin: 0 0 4px; }
.builder-toolbar-actions, .button-row { display: flex; flex-wrap: wrap; gap: 8px; }
.builder-footer { display: flex; justify-content: flex-end; gap: 10px; margin: 18px 0 30px; flex-wrap: wrap; }
.builder-list { display: grid; gap: 14px; }
.builder-item { border: 1px solid var(--border); border-radius: 14px; background: #fafbfe; padding: 14px; }
.builder-item-head { display: flex; align-items: center; justify-content: space-between; gap: 10px; margin-bottom: 12px; }
.builder-item-head strong { font-size: 1rem; }
.passage-editor { min-height: 220px; }
.question-editor textarea { min-height: 92px; }
.choice-editor-list { display: grid; gap: 8px; }
.choice-edit-row { display: grid; grid-template-columns: auto minmax(0,1fr) auto auto; gap: 8px; align-items: center; }
.static-letter { margin: 0; }
.correct-radio { display: flex; align-items: center; gap: 5px; white-space: nowrap; font-size: .82rem; font-weight: 800; }
.correct-radio input { width: auto; min-width: 18px; min-height: 18px; }
.btn-sm { min-height: 34px; padding: 7px 10px; font-size: .82rem; }
.profile-check-grid { display: grid; grid-template-columns: repeat(auto-fit,minmax(180px,1fr)); gap: 10px; }
.profile-check { display: flex; align-items: center; gap: 10px; padding: 11px; border: 1px solid var(--border); border-radius: 12px; background: #fafbfe; cursor: pointer; }
.profile-check input { width: auto; min-width: 19px; min-height: 19px; }
.profile-check span { display: flex; flex-direction: column; font-weight: 800; }
.profile-check small { color: var(--muted); font-weight: 600; }
.profile-default-row { display: grid; grid-template-columns: minmax(0,1fr) auto; gap: 10px; align-items: end; padding: 12px; border: 1px dashed #b7bfce; border-radius: 12px; background: #fafbfe; }
.settings-grid { display: grid; grid-template-columns: repeat(2,minmax(0,1fr)); gap: 8px 16px; }
.compact-empty { padding: 18px 12px; }
.question-bank-grid { display: grid; grid-template-columns: repeat(auto-fit,minmax(280px,1fr)); gap: 14px; }
.bank-card h3 { margin: 12px 0 8px; font-size: 1.02rem; line-height: 1.35; }
.bank-actions { margin-top: 14px; }
.wide-modal { width: min(1050px,100%); }

@media (max-width: 850px) {
  .library-card { grid-template-columns: 1fr; }
  .library-actions { width: 100%; grid-template-columns: repeat(4,minmax(0,1fr)); }
  .builder-toolbar { position: static; flex-direction: column; align-items: stretch; }
  .builder-toolbar-actions { justify-content: stretch; }
  .builder-toolbar-actions .btn { flex: 1; }
}
@media (max-width: 650px) {
  .library-actions { grid-template-columns: repeat(2,minmax(0,1fr)); }
  .builder-item-head { align-items: flex-start; flex-direction: column; }
  .choice-edit-row { grid-template-columns: auto minmax(0,1fr); }
  .choice-edit-row .correct-radio { grid-column: 2; }
  .settings-grid { grid-template-columns: 1fr; }
  .profile-default-row { grid-template-columns: 1fr; }
  .builder-footer { flex-direction: column; }
  .builder-footer .btn { width: 100%; }
}
.duplicate-list { display: grid; gap: 9px; margin-top: 14px; }
.duplicate-choice { appearance: none; width: 100%; text-align: left; border: 1px solid var(--border); border-radius: 12px; padding: 12px; background: #fafbfe; color: var(--text); cursor: pointer; display: flex; flex-direction: column; gap: 4px; }
.duplicate-choice:hover { border-color: #b6bff2; background: var(--primary-soft); }
.duplicate-choice span { color: var(--muted); font-size: .82rem; }

/* v1.2.1 Family Login & Internet Security */
.family-auth-wrap { min-height: calc(100vh - 150px); display: grid; place-items: center; padding: 28px 0; }
.family-auth-card { width: min(520px, 100%); text-align: center; padding: clamp(22px, 5vw, 36px); }
.family-auth-card h1 { margin: 8px 0 6px; }
.family-lock { font-size: 3.6rem; line-height: 1; }
.family-auth-form { text-align: left; margin-top: 20px; }
.family-auth-form .btn { margin-top: 4px; }
.security-note { margin-top: 16px; border: 1px solid #c7d2fe; background: #eef2ff; border-radius: 14px; padding: 13px; text-align: left; color: #3730a3; font-size: .9rem; line-height: 1.45; }
.security-footnote { margin-top: 18px; color: var(--muted); }
.remember-row { margin-top: 2px; }
.settings-stack { display: grid; gap: 16px; }
.settings-stack .settings-card { max-width: 760px; }
.security-summary { display: grid; grid-template-columns: repeat(2, minmax(0,1fr)); gap: 10px; margin: 16px 0 20px; }
.security-summary > div { display: flex; flex-direction: column; gap: 4px; border: 1px solid var(--border); border-radius: 12px; padding: 11px; background: #fafbfe; }
.security-summary strong { color: var(--muted); font-size: .78rem; text-transform: uppercase; letter-spacing: .03em; }
.security-summary span { font-weight: 800; overflow-wrap: anywhere; }
.security-password-grid { margin-top: 4px; }

@media (max-width: 620px) {
  .family-auth-wrap { min-height: auto; padding-top: 12px; }
  .security-summary { grid-template-columns: 1fr; }
}